<template>
  <div class="spec-preview">
    <img :src="skuInfo.skuDefaultImg" />
    <div class="event" @mousemove="move"></div>
    <div class="big">
      <img :src="skuInfo.skuDefaultImg" :style="{left:-2*left+'px',top:-2*top+'px'}" />
    </div>
    <div class="mask" :style="{left:left+'px',top:top+'px'}"></div>
  </div>
</template>

<script>
import { mapGetters } from 'vuex';
import { debounce } from 'lodash';
export default {
  name: 'Zoom',
  data() {
    return {
      left: 0,
      top: 0
    };
  },
  computed: {
    ...mapGetters('detail', ['skuInfo'])
  },
  methods: {
    move: debounce(function (e) {
      // 获取鼠标在当前盒子内的坐标值
      // console.log(e.offsetX, e.offsetY);
      // 1. 将产生的坐标记录一下
      let x = e.offsetX - 100;
      if (x < 0) x = 0;
      if (x > 200) x = 200;
      // console.log(x)
      let y = e.offsetY - 100;
      if (y < 0) y = 0;
      if (y > 200) y = 200;
      // 2. 将x y的值分别赋值给left top
      this.left = x;
      this.top = y;
    },1000/90)
  }
};
</script>

<style lang="less">
.spec-preview {
  position: relative;
  width: 400px;
  height: 400px;
  border: 1px solid #ccc;

  img {
    width: 100%;
    height: 100%;
  }

  .event {
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 998;
  }

  .mask {
    width: 50%;
    height: 50%;
    background-color: rgba(0, 255, 0, 0.3);
    position: absolute;
    left: 0;
    top: 0;
    display: none;
  }

  .big {
    width: 100%;
    height: 100%;
    position: absolute;
    top: -1px;
    left: 110%;
    border: 1px solid #aaa;
    overflow: hidden;
    z-index: 998;
    display: none;
    background: white;

    img {
      width: 200%;
      max-width: 200%;
      height: 200%;
      position: absolute;
      left: 0;
      top: 0;
    }
  }

  .event:hover ~ .mask,
  .event:hover ~ .big {
    display: block;
  }
}
</style>